[Differential indications for current endoprosthesis systems of the shoulder].

Modern shoulder prostheses adapt to the size, inclination, posterior offset and retrotorsion of the shoulder anatomy. Typical implants are cup prostheses for surface replacement, stemless prostheses that anchor in metaphyseal bone, anatomical prostheses using stems of different lengths, and last but not least reverse prostheses. The main reasons for implantation of shoulder prostheses are primary osteoarthritis, posttraumatic and rheumatoid arthritis, avascular necrosis, arthritis of instability and cuff defect arthropathy.Anatomical hemiprostheses should be used only if the glenoid is intact as total prostheses are functionally better as soon as the arthritis involves the glenoid. Conventional stems are cemented most of the time and cemented glenoids that are convex on the back are standard. Stemless prostheses were developed for posttraumatic indications and can often replace stemmed designs if the bone quality is good. Reverse prostheses were developed for the treatment of cuff tear arthropathies but if used as a revision implant complication rates rise and survival time is shorter.